Department of Physics, University of Trieste, P.le Europa 1, 34100 Trieste, Italy.
IOM-CNR, TASC Laboratory, Area Science Park-Basovizza, S.S 14 Km 163.5, I-34149 Trieste, Italy.
Biosensors (Basel). 2020 Aug 5;10(8):90. doi: 10.3390/bios10080090.
Electrochemical sensors are devices capable of detecting molecules and biomolecules in solutions and determining the concentration through direct electrical measurements. These systems can be miniaturized to a size less than 1 µm through the creation of small-size arrays of nanoelectrodes (NEA), offering advantages in terms of increased sensitivity and compactness. In this work, we present the fabrication of an electrochemical platform based on an array of nanoelectrodes (NEA) and its possible use for the detection of antigens of interest. NEAs were fabricated by forming arrays of nanoholes on a thin film of polycarbonate (PC) deposited on boron-doped diamond (BDD) macroelectrodes by thermal nanoimprint lithography (TNIL), which demonstrated to be a highly reliable and reproducible process. As proof of principle, gliadin protein fragments were physisorbed on the polycarbonate surface of NEAs and detected by immuno-indirect assay using a secondary antibody labelled with horseradish peroxidase (HRP). This method allows a successful detection of gliadin, in the range of concentration of 0.5-10 μg/mL, by cyclic voltammetry taking advantage from the properties of NEAs to strongly suppress the capacitive background signal. We demonstrate that the characteristics of the TNIL technology in the fabrication of high-resolution nanostructures together with their low-cost production, may allow to scale up the production of NEAs-based electrochemical sensing platform to monitor biochemical molecules for both food and biomedical applications.
电化学传感器是能够检测溶液中分子和生物分子并通过直接电测量确定浓度的设备。通过创建纳米电极（NEA）的小尺寸阵列，可以将这些系统小型化到小于 1 µm 的尺寸，从而在灵敏度和紧凑性方面具有优势。在这项工作中，我们提出了一种基于纳米电极（NEA）阵列的电化学平台的制造及其在检测感兴趣的抗原方面的可能用途。NEA 是通过在硼掺杂金刚石（BDD）上沉积的聚碳酸酯（PC）薄膜上形成纳米孔阵列，通过热纳米压印光刻（TNIL）制造的，该工艺被证明是一种高度可靠且可重复的工艺。作为原理证明，谷蛋白蛋白片段通过物理吸附在 NEA 的聚碳酸酯表面上，并通过使用辣根过氧化物酶（HRP）标记的二次抗体进行免疫间接测定来检测。该方法通过利用 NEA 强烈抑制电容背景信号的特性，通过循环伏安法成功地在 0.5-10 μg/mL 的浓度范围内检测到谷蛋白。我们证明，TNIL 技术在制造高分辨率纳米结构及其低成本生产方面的特点，可能允许将基于 NEA 的电化学传感平台的生产扩大规模，以监测食品和生物医学应用中的生化分子。
